Basic Terms of Chromatography

Analyte- It is the substance that is to be separated during
chromatography.

Chromatograph- It is equipment that enables a sophisticated separation
e.g. gas chromatographic or liquid chromatographic separation.

Stationary phase- It is the substance which is fixed in place for the
chromatography procedure. Examples include the silica layer in thin layer
chromatography.

Analytical chromatography-is used to determine the existence and
possibly also the concentration of analyte's in a sample

Bonded phase- It is a stationary phase that is covalently bonded to the
support particles or to the inside wall of the column tubing.

Chromatogram- It is the visual output of the chromatograph. In the
case of an optimal separation, different peaks or patterns on the chromatogram
correspond to different components of the separated mixture.

Chromatography-It is a physical method of separation in which the
components to be separated are distributed between two phases, one of which is
stationary (stationary phase) while the other (the mobile phase) moves in a
definite direction.

Immobilized phase- It is a stationary phase which is immobilized on
the support particles, or on the inner wall of the column tubing.

Mobile phase- It is the phase which moves in a definite direction. It
may be a liquid (LC and CEC), a gas (GC), or super-critical-fluid chromatography(SFC).
The mobile phase consists of the sample being separated/analyzed and the solvent
that moves the sample through the column. In the case of HPLC the mobile phase
consists of a non-polar solvent's) such as hexane in normal phase or polar
solvents in reverse phase chromatography and the sample being separated. The
mobile phase moves through the chromatography column (the stationary phase)
where the sample interacts with the stationary phase and is separated.

Preparative chromatography- It is used to purify sufficient quantities
of a substance for further use, rather than analysis.